New Carthage was a town situated on a peninsula - joined to the mainland to the east by a narrow isthmus. On the north side the town was protected by a large lagoon, which fed into a canal which protected the west side of the town. On the south side of the town, there was the Bay of Cartagena. As a result of this geography, New Carthage benefited for a geography that made it very difficult to assault.
Background
The Roman commander Publius Cornelius Scipio Africanus sailed to Spain in middle 210 BC, and spent the early part of the winter organizing his army and planning his assault on New Carthage. Opposing him were the three Carthaginian generals, who were on bad terms with each other, geographically scattered, and at least 10 days away from New Carthage. The Roman campaign was conducted in winter to capture new Carthage using the element of surprise. Livy mentions that the city garrison comprised 1,000 Carthaginian soldiers under the command of Mago, who picked out a further 2,000 men from the city to defend the front gate and be ready for a sally, and an unspecified amount of townsmen to watch for sudden emergencies.
Battle
Setting up camp across the isthmus with 27,500 men, Scipio isolated the town on the landward side, and with the Roman fleet blockading the town from the sea, the town was isolated from outside help. The Romans did not set up lines of circumvallation, intending to take the city by storm before help could arrive from the Carthaginian armies that were only 10 days away. The 2,000 Carthaginian armed citizens launched a sortie through the narrow east gate of the city. Their purpose was to delay the progress of Roman siege works or assaults. They got close to the Roman camp, where Scipio had been expecting such an attack. Despite possessing every advantage over the Carthaginians in numbers, training, weapons, and leadership, the Romans had to fight hard and long against the skilled militia. Scipio fed in more maniples to the battle from his reserve and the Carthaginians broke and fled back to the city. Scipio launched an assault over the isthmus, while the fleet attacked from the southern side. A hail of Carthaginian missiles beat back every Roman assault with heavy casualties. Scipio renewed the attack later in the day, with the addition of a party attacking through the lagoon on the northern side. Aided by a wind squall, the party managed to scale the undefended northern wall and attacked the rear of the defenders defending the isthmus. At the same time, the naval forces managed to penetrate the town from the south. Polybius gives a description of how Scipio Africanus stormed New Carthage:
Aftermath
With the fall of New Carthage, the Romans forced the Carthaginians to surrender the entire eastern coast of Spain, as well as capturing a large amount of military stores and the silver mines located nearby.
